The present invention relates generally to electrical communications systems and, more particularly, to condition responsive indicating systems with particular safety functions.
As society has moved into the 21st Century, some of its disaffected members have resorted to acts of extreme violence and terror as a way of being heard. Some of these acts have taken the lives of thousands of people and have injured thousands more. Unfortunately, no one foresees an end to acts such as these. At this point in time, one can only hope to be forewarned a reasonable period of time in advance of such an act so that precautions can be taken to altogether avoid or minimize the expected harm.
To a certain extent, mass mediaxe2x80x94radio and, television in particularxe2x80x94is effective in rapidly alerting the public of impending, ongoing and completed acts of terrorism. The principal drawback of relying principally upon radio and television to provide alerts of terrorist activities is that the alerts cannot be transmitted to receivers that are turned off. Of course, most users do not keep their radios and televisions turned on at all times, and broadcasters lack the ability to energize conventional radios and televisions. Thus, it can be expected that many would miss critical broadcast alerts about impending and ongoing terrorist activities and would be harmed as a result.
In light of the drawbacks associated with using broadcast media to rapidly and accurately disseminate information important to public health and welfare, it is a principal object of the invention to provide an emergency warning system that could be used only by authorized personnel to notify specified people of impending dangers. These dangers might include: fires, explosions, chemical spills, hostage takings, radiation leaks, and the spread of biological agents or gasses to name a few. Apart from news regarding dangers, time-critical information related to weather and earth movements can be delivered to interested parties by modified forms of the system.
It is a further object of the invention to provide an emergency warning system of the type described that can be employed to provide time-critical information wherever they may be located, whether at home, at work, in a vehicle, or otherwise.
It is another object of the invention to provide an emergency warning system of the type described that alerts users of its activation with audible and visual alarms. Once the alarms have sounded, detailed information may be obtained in a visual and audible manner. Message transmission can be selectively terminated by a user.
It is an object of the invention to provide improved elements and arrangements thereof in an emergency warning system for the purposes described that is rugged in construction, inexpensive to manufacture, and dependable in use.
Briefly, the emergency warning system in accordance with this invention achieves the intended objects by featuring a transmitter for broadcasting a radio frequency (RF) communication signal carrying information produced by a sensor to a receiver. The receiver is connected to another transmitter so as to permit the broadcast an RF alert signal carrying public warnings as required by the content of the communication signal to a desktop receiver or a pocket pager. Upon detecting the alert signal, the desktop receiver and the pager issue audible and visual alarms.